Organic light emitting display apparatus

ABSTRACT

An organic light emitting display apparatus includes a substrate; an anode electrode on the substrate; an auxiliary electrode on the substrate; an organic emission layer on the anode electrode; a cathode electrode on the organic emission layer and on the auxiliary electrode; an insulating bank on the auxiliary electrode, the bank overlapping a first portion of the auxiliary electrode and exposing a second portion of the auxiliary electrode; a first partition wall on the auxiliary electrode; a second partition wall on the first partition wall and covering the exposed second portion of the auxiliary electrode in plan view. A separation space is between the second partition wall and the bank, the cathode electrode is electrically connected to the auxiliary electrode through the separation space between the second partition wall and the bank, and the second partition wall is supported by the first partition wall and the bank.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application of U.S. application Ser. No.14/983,899, filed Dec. 30, 2015, and also claims priority from KoreanPatent Application No. 10-2015-0076678, filed on May 29, 2015, both ofwhich are hereby incorporated by reference as if fully set forth herein.

BACKGROUND Field of the Disclosure

The present disclosure relates to an organic light emitting displayapparatus, and more particularly, to a top emission type organic lightemitting display apparatus.

Discussion of the Related Art

Organic light emitting display apparatuses are self-emitting apparatusesand typically have low power consumption, a fast response time, highemission efficiency, high luminance, and a wide viewing angle.

The organic light emitting display apparatuses are typically classifiedinto a top emission type and a bottom emission type, based on atransmission direction of light emitted from an organic light emittingdevice. In the bottom emission type, a circuit element is disposedbetween an emission layer and an image displaying surface, and for thisreason, an aperture ratio is lowered. On the other hand, in the topemission type, the circuit element is not disposed between the emissionlayer and the image displaying surface, and thus, an aperture ratio isenhanced.

FIG. 1 is a cross-sectional view of a related art top emission typeorganic light emitting display apparatus.

As seen in FIG. 1, a thin film transistor (TFT) T, which includes anactive layer 11, a gate insulation layer 12, a gate electrode 13, aninterlayer dielectric 14, a source electrode 15, and a drain electrode16, is formed on a substrate 10, and a passivation layer 20 and aplanarization layer 30 are sequentially formed on the TFT T.

An anode electrode 40 and an auxiliary electrode 50 are formed on theplanarization layer 30. The auxiliary electrode 50 decreases aresistance of a cathode electrode 80 as will be described below.

A bank 60 is formed on the anode electrode 40 and the auxiliaryelectrode 50 and defines a pixel area by its absence. An organicemission layer 70 is formed in the pixel area defined by the bank 60,and the cathode electrode 80 is formed on the organic emission layer 70.

In the top emission type, light emitted from the organic emission layer70 passes through the cathode electrode 80 and travels. Therefore, thecathode electrode 80 is formed of a transparent conductive material, butfor this reason, a resistance of the cathode electrode 80 typically isincreased. To decrease the resistance of the cathode electrode 80, thecathode electrode 80 is connected to the auxiliary electrode 50.

The related art top emission type organic light emitting displayapparatus may have at least the following problems.

The related art organic light emitting display apparatus is an organiclight emitting display apparatus to which a top emission type isapplied, and has a drawback where it is difficult to deposit the organicemission layer 70. For example, in the related art organic lightemitting display apparatus, an additional process may be needed todeposit the organic emission layer 70 on only the anode electrode 40.Also, in a case of blanket-depositing the organic emission layer 70, theauxiliary electrode 50 cannot be connected to the cathode electrode 80.Furthermore, because the organic emission layer 70 is not patterned tobe separated in each of a plurality of pixels, defective driving canoccur.

SUMMARY

Accordingly, the present disclosure is directed to providing an organiclight emitting display apparatus that substantially obviates one or moreproblems due to limitations and disadvantages of the related art.

To achieve these and other advantages and in accordance with the purposeof the invention, as embodied and broadly described herein, there isprovided an organic light emitting display apparatus, comprising asubstrate; an anode electrode on the substrate; an auxiliary electrodeon the substrate; an organic emission layer on the anode electrode; acathode electrode on the organic emission layer and on the auxiliaryelectrode; an insulating bank on the auxiliary electrode, the bankoverlapping a first portion of the auxiliary electrode and exposing asecond portion of the auxiliary electrode; a first partition wall on theauxiliary electrode; a second partition wall on the first partition walland covering the exposed second portion of the auxiliary electrode inplan view, wherein a separation space is between the second partitionwall and the bank; the cathode electrode is electrically connected tothe auxiliary electrode through the separation space between the secondpartition wall and the bank; and the second partition wall is supportedby the first partition wall and the bank.

Additional advantages and features of the invention will be set forth inpart in the description which follows and in part will become apparentto those having ordinary skill in the art upon examination of thefollowing or may be learned from practice of the invention. Theobjectives and other advantages of the invention may be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description of the present disclosure areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiments of the invention andtogether with the description serve to explain the principles ofembodiments of the invention. In the drawings:

FIG. 1 is a cross-sectional view of a related art top emission typeorganic light emitting display apparatus;

FIG. 2 is a cross-sectional view of an organic light emitting displayapparatus according to an example embodiment of the present invention;

FIG. 3 is a plan view of an organic light emitting display apparatusaccording to an example embodiment of the present invention;

FIG. 4 is a plan view of an organic light emitting display apparatusaccording to another example embodiment of the present invention;

FIG. 5 is a plan view of an organic light emitting display apparatusaccording to another example embodiment of the present invention;

FIGS. 6A to 6C are cross-sectional views of an organic light emittingdisplay apparatus according to another example embodiment of the presentinvention;

FIG. 7 is a cross-sectional view of an organic light emitting displayapparatus according to another example embodiment of the presentinvention; and

FIG. 8 is a cross-sectional view of an organic light emitting displayapparatus according to another example embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE ILLUSTRATED INVENTION

Reference will now be made in detail to example embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Where possible, the same reference numbers may be usedthroughout the drawings to refer to the same or like parts.

Advantages and features of embodiments of the present invention, andimplementation methods thereof, will be described through the followingwith reference to the accompanying drawings. The present invention may,however, be embodied in different forms and should not be construed aslimited to the embodiments set forth herein. Rather, these embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the present invention to those skilled inthe art.

A shape, a size, a ratio, an angle, and a number disclosed in thedrawings for describing embodiments of the present invention are merelyan example, and thus, the present invention is not limited to theillustrated details. In the following description, when the detaileddescription of the relevant known function or configuration isdetermined to unnecessarily obscure the disclosure, detailed descriptionmay be omitted.

Features of various embodiments of the present invention may bepartially or overall coupled to or combined with each other, and may bevariously inter-operated with each other and driven technically as thoseskilled in the art can sufficiently understand. The embodiments of thepresent invention may be carried out independently from each other, ormay be carried out together in co-dependent relationship.

Hereinafter, example embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

FIG. 2 is a cross-sectional view of an organic light emitting displayapparatus according to an example embodiment of the present invention.

As seen in FIG. 2, a thin film transistor (TFT) T, an auxiliary line300, a passivation layer 165, a planarization layer 170, an anodeelectrode 180, an auxiliary electrode 190, a bank 220, a partition wall230, an organic emission layer 240, and a cathode electrode 250 may beformed on a substrate 100.

The TFT T may include an active layer 110, a gate insulation layer 120,a gate electrode 130, an interlayer dielectric 140, a source electrode150, and a drain electrode 160.

The active layer 110 may be formed on the substrate 100. The activelayer 110 may be formed of a silicon-based semiconductor material, ormay be formed of an oxide-based semiconductor material. Although notshown, a light shielding layer may be further formed between thesubstrate 100 and the active layer 110, and in this case, external lightincident through a bottom of the substrate 100 is blocked by the lightshielding layer, thereby preventing the active layer 110 from beingdamaged by external light.

The gate insulation layer 120 may be formed on the active layer 110. Thegate insulation layer 120 may insulate the active layer 110 from thegate electrode 130. The gate insulation layer 120 may be formed of aninorganic insulating material, for example, silicon oxide (SiOx),silicon nitride (SiNx), or a multilayer thereof, but is not limitedthereto.

The gate electrode 130 may be formed on the gate insulation layer 120.The gate electrode 130 may be formed to overlap the active layer 110with the gate insulation layer 120 therebetween. The gate electrode 130may be formed of a single layer or a multilayer formed of one ofmolybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti),nickel (Ni), neodymium (Nd), copper (Cu), or an alloy thereof, but isnot limited thereto.

The interlayer dielectric 140 may be formed on the gate electrode 130.The interlayer dielectric 140 may be formed of the same inorganicinsulating material as that of the gate insulation layer 120, forexample, silicon oxide (SiOx), silicon nitride (SiNx), or a multilayerthereof, but is not limited thereto.

The source electrode 150 and the drain electrode 160 may be formed toface each other on the interlayer dielectric 140. A first contact holeCH1 exposing one end region of the active layer 110 and a second contacthole CH2 exposing the other end region of the active layer 110 may beincluded in the gate insulation layer 120 and the interlayer dielectric140. The source electrode 150 may be connected to the other end regionof the active layer 110 through the second contact hole CH2, and thedrain electrode 160 may be connected to the one end region of the activelayer 110 through the first contact hole CH1.

A structure of the TFT T is not limited to the illustrated structure,and may be variously modified to structures known to those skilled inthe art. For example, a top gate structure where the gate electrode 130is formed on the active layer 110 is illustrated in the drawing, but theTFT T may be formed in a bottom gate structure where the gate electrode130 is formed under the active layer 110.

The auxiliary line 300 may be disposed on the same layer as a layer onwhich the source electrode 150 and the drain electrode 160 are disposed(e.g., on interlayer dielectric 140), and may be disposed to beseparated from the source electrode 150 and the drain electrode 160. Theauxiliary line 300 may be formed through the same process simultaneouslywith the source electrode 150 and the drain electrode 160, and may beformed of the same material as that of the source electrode 150 and thedrain electrode 160. The auxiliary line 300 may be connected to thebelow-described auxiliary electrode 190 through a fourth contact holeCH4. Because the auxiliary line 300 is connected to the auxiliaryelectrode 190 through the fourth contact hole CH4, resistances of theauxiliary electrode 190 and the cathode electrode 250 may be lowered.

The passivation layer 165 may be formed on the TFT T, and in moredetail, may be formed on tops of the source electrode 150, the drainelectrode 160, and the auxiliary line 300. The passivation layer 165protects the TFT T. The passivation layer 165 may be formed of aninorganic insulating material (for example, SiOx and SiNx), but is notlimited thereto.

The planarization layer 170 may be formed on the passivation layer 165.The planarization layer 170 may planarize an upper surface of thesubstrate 100 including the TFT T. The planarization layer 170 may beformed of an organic insulating material such as acryl resin, epoxyresin, phenolic resin, polyamide resin, polyimide resin, or the like,but is not limited thereto.

The anode electrode 180 and the auxiliary electrode 190 may be formed onthe planarization layer 170. That is, the anode electrode 180 and theauxiliary electrode 190 may be formed on the same layer. A third contacthole CH3 exposing the source electrode 150 may be included in thepassivation layer 165 and the planarization layer 170, and the sourceelectrode 150 may be connected to the anode electrode 180 through thethird contact hole CH3. Also, the fourth contact hole CH4 exposing theauxiliary line 300 may be included in the passivation layer 165 and theplanarization layer 170, and the auxiliary line 300 may be connected tothe auxiliary electrode 190 through the fourth contact hole CH4.

The bank 220 may be formed on the anode electrode 180 and the auxiliaryelectrode 190. The bank 220 may be formed on one side and the other sideof the anode electrode 180 (e.g., opposite sides) to leave tops of theanode electrode 180 and the auxiliary electrode 190 exposed, and tocover side surfaces of the anode electrode 180 and the auxiliaryelectrode 190. Because the bank 220 is formed to expose the top of theanode electrode 180, an area where an image is displayed is secured.Also, because the bank 220 is formed to expose the tops of the anodeelectrode 180 and the auxiliary electrode 190, an electrical connectionspace between the auxiliary electrode 190 and the cathode electrode 250is made available.

Moreover, the bank 220 may be formed between the anode electrode 180 andthe auxiliary electrode 190, and may insulate the anode electrode 180from the auxiliary electrode 190. The bank 220 may be formed of anorganic insulating material such as polyimide resin, acryl resin,benzocyclobutene (BCB), or the like, but is not limited thereto.

The partition wall 230 may be formed on the auxiliary electrode 190. Thepartition wall 230 may be separated from the bank 220 by a certaindistance, and the auxiliary electrode 190 may be electrically connectedto the cathode electrode 250 through a separation space between thepartition wall 230 and the bank 220.

In a related art organic light emitting display apparatus, an auxiliaryelectrode is electrically connected to a cathode electrode withoutforming a partition wall. On the other hand, according to an exampleembodiment of the present invention, the partition wall 230 is formed,and thus, the organic emission layer 240 is more easily deposited. Thiswill be described below in detail.

If the partition wall 230 is not formed, a mask pattern, which covers atop of the auxiliary electrode 190, is needed in depositing the organicemission layer 240, in order for the top of the auxiliary electrode 190not to be covered by the organic emission layer 240. However, if thepartition wall 230 is formed, a top of the partition wall 230 may act aseaves in depositing the organic emission layer 240. Thus, because theorganic emission layer 240 is not deposited under the eaves, the maskpattern which covers the top of the auxiliary electrode 190 is notneeded. That is, with respect to a case where the organic light emittingdisplay apparatus is seen from the front thereof, when the top of thepartition wall 230 that acts as eaves is formed to cover a separationspace between the partition wall 230 and the bank 220, the organicemission layer 240 may not penetrate into the separation space betweenthe partition wall 230 and the bank 220, and thus, the auxiliaryelectrode 190 may be exposed in the separation space between thepartition wall 230 and the bank 220. For example, the organic emissionlayer 240 may be formed by a deposition process, such as an evaporationprocess, which is excellent in straightness of a deposited material, andthus, the organic emission layer 240 cannot be deposited in theseparation space between the partition wall 230 and the bank 220.

As described above, a width of the top of the partition wall 230 may beformed greater than that of a bottom of the partition wall 230, in orderfor the top of the partition wall 230 to act as the eaves. The partitionwall 230 may include a lower first partition wall 231 and an uppersecond partition wall 232. The first partition wall 231 may be formed ona top of the auxiliary electrode 190 and may be formed of the samematerial as that of the bank 220 through the same process as that of thebank 220. The second partition wall 232 may be formed on a top of thefirst partition wall 231. A width of a top of the second partition wall232 may be formed greater than that of a bottom of the second partitionwall 232, and particularly, the top of the second partition wall 232 maybe formed to cover the separation space between the partition wall 230and the bank 220 and may act as eaves.

In this case, the first partition wall 231 may be formed not to overlapthe fourth contact hole CH4 that connects the auxiliary electrode 190 tothe auxiliary line 300. When the fourth contact hole CH4 and the firstpartition wall 231 are formed to overlap each other, the auxiliaryelectrode 190 formed under the first partition wall 231 may notuniformly be formed due to the fourth contact hole CH4, and for thisreason, the first partition wall 231 may not be uniformly formed. Whenthe first partition wall 231 is not uniformly formed, the secondpartition wall 232 formed on the first partition wall 231 may beinclined, and the organic emission layer 240 may be formed on theauxiliary electrode 190, thereby causing a defect where the cathodeelectrode 250 may not be connected to the auxiliary electrode 190.

The organic emission layer 240 may be formed on the anode electrode 180.The organic emission layer 240 may include a hole injection layer, ahole transport layer, an emission layer, an electron transport layer,and an electron injection layer. The organic emission layer 240 may bemodified to have various structures known to those skilled in the art.

The organic emission layer 240 may extend to the top of the bank 220.However, the organic emission layer 240 may not extend to the top of theauxiliary electrode 190 and cover the top of the auxiliary electrode190. This is because when the organic emission layer 240 covers the topof the auxiliary electrode 190, it may be difficult to electricallyconnect the auxiliary electrode 190 to the cathode electrode 250. Asdescribed above, the organic emission layer 240 may be formed by adeposition process without a mask that covers the top of the auxiliaryelectrode 190, and in this case, the organic emission layer 240 may beformed on the top of the partition wall 230.

The cathode electrode 250 may be formed on the organic emission layer240. The cathode electrode 250 may be formed on a surface from whichlight is emitted, and thus may be formed of a transparent conductivematerial. Because the cathode electrode 250 is formed of a transparentconductive material, a resistance of the cathode electrode 250 is high,and for this reason, in order to lower the resistance of the cathodeelectrode 250, the cathode electrode 250 may be connected to theauxiliary electrode 190. That is, the cathode electrode 250 may beconnected to the auxiliary electrode 190 through the separation spacebetween the partition wall 230 and the bank 220. The cathode electrode250 may be formed by a deposition process, such as a sputtering process,which is not good in straightness of a deposited material. Thus, thecathode electrode 250 may be deposited in the separation space betweenthe partition wall 230 and the bank 220 in a process of depositing thecathode electrode 250.

Although not shown, an encapsulation layer may be further formed on thecathode electrode 250 and prevents penetration of water. Theencapsulation layer may use various materials known to those skilled inthe art. Also, although not shown, a color filter may be further formedfor each pixel and on the cathode electrode 250, and in this case, whitelight may be emitted from the organic emission layer 240.

FIG. 3 is a plan view of an organic light emitting display apparatusaccording to an example embodiment of the present invention.

FIG. 3 illustrates a plan view of the above-described organic lightemitting display apparatus of FIG. 2. Thus, like reference numeralsrefer to like elements, and in a material and a structure of eachelement, the same or similar descriptions are not repeated.

As seen in FIG. 3, the organic light emitting display apparatusaccording to an embodiment of the present invention may include an anodeelectrode 180, an auxiliary electrode 190, a bank 220, a first partitionwall 231, a second partition wall 232, and an auxiliary line 300.

The anode electrode 180 may be formed in plurality on a substrate of theorganic light emitting display apparatus. A plurality of the auxiliarylines 300 may be respectively formed between the plurality of anodeelectrodes 180 and arranged in one direction to have a stripe structure.

The auxiliary electrode 190 may be formed on the auxiliary line 300 in arectangular shape. However, the present embodiment is not limitedthereto.

The bank 220 may be formed to overlap a portion of the auxiliaryelectrode 190.

The first partition wall 231 may be formed at a center portion of theauxiliary electrode 190 to support the second partition wall 232. Thefirst partition wall 231 and the second partition wall 232 may be formedin an island shape on the auxiliary electrode 190 to be separated fromthe other elements.

A fourth contact hole CH4 may be formed on the auxiliary electrode 190and may be connected to the auxiliary line 300.

A cathode electrode may be formed without an organic emission layerbeing formed in a partial region (i.e., a portion of the auxiliaryelectrode 190 overlapping the second partition wall 232) other than apartial region where the first partition wall 231 is formed, in a regionof the auxiliary electrode 190 corresponding to the second partitionwall 232. Thus, the auxiliary electrode 190 may be electricallyconnected to the cathode electrode.

As described above, if the second partition wall 232 is formed, a top ofthe second partition wall 232 may act as eaves in depositing the organicemission layer, and thus, because the organic emission layer is notdeposited under the eaves, a mask pattern which covers a top of theauxiliary electrode 190 is not needed.

However, a width of a top of the second partition wall 232 may be formedgreater than that of a bottom of the second partition wall 232, andbecause the first partition wall 231 is formed under the secondpartition wall 232 according to a size of the bottom of the secondpartition wall 232, the first partition wall 231 may unstably supportthe second partition wall 232. Due to such a problem, if the firstpartition wall 231 cannot support the second partition wall 232, the topof the second partition wall 232, acting as eaves, may not cover aseparation space between the partition wall and the bank 220, and forthis reason, the organic emission layer may penetrate into theseparation space between the partition wall and the bank 220. Therefore,the auxiliary electrode 190 may not be exposed, causing a defect wherethe cathode electrode cannot be electrically connected to the auxiliaryelectrode 190. Also, when a total size of the auxiliary electrode 190increases for forming the second partition wall 232 with a stable size,a size of the anode electrode 180 formed on the same layer as a layer onwhich the auxiliary electrode 190 is disposed may be reduced, causing areduction in an aperture ratio.

FIG. 4 is a plan view of an organic light emitting display apparatusaccording to another example embodiment of the present invention.

FIG. 4 illustrates a plan view of the above-described organic lightemitting display apparatus of FIG. 2. Thus, like reference numeralsrefer to like elements, and in a material and a structure of eachelement, the same or similar descriptions are not repeated.

As seen in FIG. 4, the organic light emitting display apparatus mayinclude an anode electrode 180, an auxiliary electrode 190, a bank 220,a first partition wall 231, a second partition wall 232, and anauxiliary line 300. Elements other than the first partition wall 231 andthe second partition wall 232 may be the same as those of theabove-described organic light emitting display apparatus of FIG. 3, andthus, their detailed descriptions are not repeated.

The first partition wall 231 of the organic light emitting displayapparatus of FIG. 3 is formed in an island shape on the auxiliaryelectrode 190 to be separated from the other elements. On the otherhand, both ends of the first partition wall 231 of the organic lightemitting display apparatus according to another example embodiment ofthe present invention may contact the bank 220. Therefore, according toanother example embodiment, the first partition wall 231 may not beformed in an island shape on the auxiliary electrode 190 to be separatedfrom the other elements, but may be formed to contact the bank 220, andthus, the first partition wall 231 may stably support the secondpartition wall 232.

Moreover, the second partition wall 232 of the organic light emittingdisplay apparatus of FIG. 3 may be formed on a top of the firstpartition wall 231 to be supported by only the first partition wall 231.On the other hand, the second partition wall 232 of the organic lightemitting display apparatus according to another example embodiment ofthe present invention may be formed to contact the bank 220, and thepartition wall 231 may be formed on the same layer as a layer on whichthe bank 220 is disposed, whereby the second partition wall 232 is morestably supported by the first partition wall 231 and the bank 220. Forthis reason, a defect where the cathode electrode cannot electrically beconnected to the auxiliary electrode 190 may be prevented. Also, thesecond partition wall 232 may be stably formed even without any increasein a total size of the auxiliary electrode 190, and thus may not affecta size of the anode electrode 180 which is formed on the same layer as alayer thereof, thereby preventing an aperture ratio from being reduced.

The first partition wall 231 may include a portion contacting the bank220 and another portion which does not contact the bank 220. Theauxiliary electrode 190 may be formed to be exposed in a region betweenthe bank 220 and the other portion of the first partition wall 231 whichdoes not contact the bank 220. Therefore, the exposed auxiliaryelectrode 190 may be electrically connected to the cathode electrode,thereby lowering a resistance.

An organic emission layer may not be formed in an exposed region of theauxiliary electrode 190, where the first partition wall 231 and the bank220 are not formed. Accordingly, the cathode electrode may beelectrically connected to the auxiliary electrode 190 in the exposedregion of the auxiliary electrode 190.

FIG. 5 is a plan view of an organic light emitting display apparatusaccording to another example embodiment of the present invention.

FIG. 5 illustrates a plan view of the above-described organic lightemitting display apparatus of FIG. 2. Thus, like reference numeralsrefer to like elements, and in a material and a structure of eachelement, the same or similar descriptions are not repeated.

As seen in FIG. 5, the organic light emitting display apparatus mayinclude an anode electrode 180, an auxiliary electrode 190, a bank 220,a first partition wall 231, a second partition wall 232, and anauxiliary line 300. Elements other than the auxiliary line 300 may bethe same as those of the above-described organic light emitting displayapparatus of FIG. 4, and thus, their detailed descriptions are notrepeated.

The auxiliary lines 300 of the organic light emitting display apparatusof FIG. 4 are respectively formed between the plurality of anodeelectrodes 180 and arranged in one direction to have the stripestructure. On the other hand, in the organic light emitting displayapparatus according to the example embodiment of FIG. 5, a plurality ofthe auxiliary lines 300 may be formed in a mesh structure where theplurality of auxiliary lines 300 are arranged to intersect each otherbetween a plurality of the anode electrodes 180. Therefore, an area ofeach of the auxiliary lines 300 is larger in a case where the auxiliarylines 300 are formed in the mesh structure, than in a case where theauxiliary lines 300 are formed in the stripe structure, and thus, aresistance of the organic light emitting display apparatus according toanother example embodiment of the present invention may be furtherreduced.

The auxiliary electrode 190 may be formed at a portion where theauxiliary lines 300 intersect each other.

FIGS. 6A to 6C are cross-sectional views of an organic light emittingdisplay apparatus according to another example embodiment of the presentinvention, and illustrate a cross-sectional view of the above-describedauxiliary electrode of FIG. 5. Thus, like reference numerals refer tolike elements, and in a material and a structure of each element, thesame or similar descriptions are not repeated.

FIG. 6A illustrates a cross-sectional surface taken along line A-A ofFIG. 5. As seen in FIG. 6A, the anode electrode 180 and the auxiliaryelectrode 190 may be formed on a planarization layer 170 to be separatedfrom each other. The bank 220 may be formed between the anode electrode180 and the auxiliary electrode 190, and may insulate the anodeelectrode 180 from the auxiliary electrode 190. The first partition wall231 may be formed in an island shape on an exposed portion of a top ofthe auxiliary electrode 190, and the second partition wall 232 may beformed on a top of the first partition wall 231.

FIG. 6B illustrates a cross-sectional surface taken along line B-B ofFIG. 5. As seen in FIG. 6B, the anode electrode 180, the auxiliaryelectrode 190, and the bank 220 may be formed on the planarization layer170. Because line B-B is located in a region which is exposed withoutthe first partition wall 231 being formed in the auxiliary electrode190, the first partition wall 231 is not illustrated. Both ends of thesecond partition wall 232 may be formed to contact the bank 220.

FIG. 6C illustrates a cross-sectional surface taken along line C-C ofFIG. 5. As seen in FIG. 6C, the anode electrode 180, the auxiliaryelectrode 190, and the bank 220 may be formed on the planarization layer170. The first partition wall 231 may extend and may be connected to thebank 220, and the second partition wall 232 may be formed to besupported by the first partition wall 231 and the bank 220.

FIG. 7 is a cross-sectional view of an organic light emitting displayapparatus according to another example embodiment of the presentinvention.

Except for a first anode electrode 180, a second anode electrode 200, afirst auxiliary electrode 190, and a second auxiliary electrode 210, theorganic light emitting display apparatus of FIG. 7 may be the same asthe above-described organic light emitting display apparatus of FIG. 2,and thus, repetitive descriptions are not provided.

The first anode electrode 180 and the first auxiliary electrode 190 maybe formed on the planarization layer 170. That is, the first anodeelectrode 180 and the first auxiliary electrode 190 may be formed on thesame layer. A third contact hole CH3 exposing the source electrode 150may be included in the above-described passivation layer 165 andplanarization layer 170, and the source electrode 150 may be connectedto the first anode electrode 180 through the third contact hole CH3.

The first anode electrode 180 may include a first lower anode electrode181 and a first upper anode electrode 182.

The first lower anode electrode 181 may be formed between theplanarization layer 170 and the first upper anode electrode 182, and mayenhance an adhesive force between the planarization layer 170 and thefirst upper anode electrode 182. Also, the first lower anode electrode181 may protect a bottom of the first upper anode electrode 182, therebypreventing the bottom of the first upper anode electrode 182 from beingcorroded.

The first upper anode electrode 182 may be formed on a top of the firstlower anode electrode 181. The first upper anode electrode 182 may beformed of metal which is relatively lower in resistance than the firstlower anode electrode 181.

Similarly to the above-described first anode electrode 180, the firstauxiliary electrode 190 may include a first lower auxiliary electrode191 and a second upper auxiliary electrode 192.

The first lower auxiliary electrode 191 may be formed between theplanarization layer 170 and the first upper auxiliary electrode 192. Thefirst lower auxiliary electrode 191 may enhance an adhesive forcebetween the planarization layer 170 and the first upper auxiliaryelectrode 192, and may prevent a bottom of the first upper auxiliaryelectrode 192 from being corroded.

The first upper auxiliary electrode 192 may be formed of low-resistancemetal on a top of the first lower auxiliary electrode 191.

The second anode electrode 200 may be formed to cover a top and a sidesurface of the first anode electrode 180, thereby preventing the top andside surfaces of the first anode electrode 180 from being corroded.

The second anode electrode 200 may include a second lower anodeelectrode 201, a second center anode electrode 202, and a second upperanode electrode 203.

The second lower anode electrode 201 may be formed between the firstanode electrode 180 and the second center anode electrode 202. Thesecond lower anode electrode 201 may be formed to cover the top and sidesurface of the first anode electrode 180, thereby preventing the firstanode electrode 180 from being corroded.

The second center anode electrode 202 may be formed between the secondlower anode electrode 201 and the second upper anode electrode 203. Thesecond center anode electrode 202 may be formed of a material which islower in resistance than, and better in reflectivity than, the secondlower anode electrode 201 and the second upper anode electrode 203.

The second upper anode electrode 203 may be formed on a top of thesecond center anode electrode 202, thereby preventing the top of thesecond center anode electrode 202 from being corroded.

The second auxiliary electrode 210 may be formed on a top of the firstauxiliary electrode 190. The second auxiliary electrode 210 may beformed on the same layer as a layer on which the second anode electrode200 is disposed. The second auxiliary electrode 210 may be formed tocover a top and a side surface of the first auxiliary electrode 190,thereby preventing the top and side surfaces of the first auxiliaryelectrode 190 from being corroded. The second auxiliary electrode 210may lower a resistance of the cathode electrode 250 along with the firstauxiliary electrode 190.

The second auxiliary electrode 210 may include a second lower auxiliaryelectrode 211, a second center auxiliary electrode 212, and a secondupper auxiliary electrode 213.

The second lower auxiliary electrode 211 may be formed between the firstauxiliary electrode 190 and the second center auxiliary electrode 212.The second lower auxiliary electrode 211 may be formed to cover the topand side surfaces of the first auxiliary electrode 190, therebypreventing the first auxiliary electrode 190 from being corroded.

The second center auxiliary electrode 212 may be formed between thesecond lower auxiliary electrode 211 and the second upper auxiliaryelectrode 213. The second center auxiliary electrode 212 may be formedof a material that is lower in resistance than, and better inreflectivity than, the second lower auxiliary electrode 211 and thesecond upper auxiliary electrode 213.

The second upper auxiliary electrode 213 may be formed on a top of thesecond center auxiliary electrode 212, thereby preventing the top of thesecond center auxiliary electrode 212 from being corroded.

FIG. 8 is a cross-sectional view of an organic light emitting displayapparatus according to another example embodiment of the presentinvention.

Except for a first connection line 185, a second connection line 195,and a second planarization layer 175, the organic light emitting displayapparatus of FIG. 8 may be the same as the above-described organic lightemitting display apparatus of FIG. 2, and thus, repetitive descriptionsare not provided.

In the above-described organic light emitting display apparatus of FIG.7, the second anode electrode 200 and the second auxiliary electrode 210are respectively formed on the first anode electrode 180 and the firstauxiliary electrode 190, and thus, resistances of the anode electrode180 and the cathode electrode 250 may be lowered. However, because theauxiliary electrode 190 and the anode electrode 180 are formed on thesame layer, a space for forming the anode electrode 180 and theauxiliary electrode 190 may be limited. In contrast, in the organiclight emitting display apparatus of FIG. 8 according to another exampleembodiment, the first connection line 185 connected to the anodeelectrode 180 may be formed under the anode electrode 180, and thesecond connection line 195 connected to the auxiliary electrode 190 maybe formed under the auxiliary electrode 190. The anode electrode 180 andthe auxiliary electrode 190 are respectively connected to the firstconnection line 185 and the second connection line 195, and thus may bebroad in area. Accordingly, resistances of the anode electrode 180 andthe cathode electrode 250 may be further reduced.

The first connection line 185 and the second connection line 195 may beformed on the first planarization layer 170. That is, the firstconnection line 185 and the second connection line 195 may be formed onthe same layer to be separated from each other. A third contact hole CH3exposing the source electrode 150 may be included in the passivationlayer 165 and the first planarization layer 170, and the sourceelectrode 150 may be connected to the first connection line 185 throughthe third contact hole CH3. Also, a fourth contact hole CH4 exposing theauxiliary line 300 may be included in the passivation layer 165 and thefirst planarization layer 170, and the auxiliary line 300 may beconnected to the second connection line 195 through the fourth contacthole CH4.

The second planarization layer 175 may be formed on the first and secondconnection lines 185 and 195. The anode electrode 180 and the auxiliaryelectrode 190 may be formed on the second planarization layer 175. Afifth contact hole CH5 exposing the first connection line 185 may beincluded in the second planarization layer 175, and the first connectionline 185 may be connected to the anode electrode 180 through the fifthcontact hole CH5. That is, the anode electrode 180 may be connected tothe source electrode 150 through the first connection line 185. Also, asixth contact hole CH6 exposing the second connection line 195 may beincluded in the second planarization layer 175, and the secondconnection line 195 may be connected to the auxiliary electrode 190through the sixth contact hole CH6. That is, the auxiliary electrode 190may be connected to the auxiliary line 300 through the second connectionline 195.

As described above, according to example embodiments of the presentinvention, the partition wall may be stably formed in the existing sizeof the auxiliary electrode without reduction in an aperture ratio.

Moreover, according to example embodiments of the present invention, theorganic emission layer may be formed without a mask pattern covering atop of the auxiliary electrode, and thus, an increase in the complexityor time for the mask process may be prevented.

Moreover, according to example embodiments of the present invention, thefirst partition wall may stably support the second partition wall,thereby preventing a defect.

Moreover, according to example embodiments of the present invention, twoanode electrodes (for example, the first and second anode electrodes)may be stack-formed for lowering the resistance of the anode electrode,and thus, the desired resistance characteristic of the anode electrodemay be more easily obtained.

Moreover, according to example embodiments of the present invention, twoauxiliary electrodes (for example, the first and second auxiliaryelectrodes) may be stack-formed for lowering the resistance of thecathode electrode, and thus, the desired resistance characteristic ofthe auxiliary electrode may be more easily obtained.

Moreover, according to example embodiments of the present invention, theauxiliary line may be connected to the auxiliary electrode by theconnection line, and thus, the desired resistance characteristic of theauxiliary electrode may be more easily obtained.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. An organic light emitting display apparatus, comprising: a substrate;an auxiliary line on the substrate; an anode electrode on the substrate;an auxiliary electrode on the substrate; an organic emission layer onthe anode electrode; a cathode electrode on the organic emission layerand on the auxiliary electrode; an bank overlapping with a first portionof the auxiliary electrode and exposing a second portion of theauxiliary electrode; a partition wall on the second portion of theauxiliary electrode; and a separation space between the partition walland the bank, the cathode electrode being electrically connected to theauxiliary electrode through the separation space, wherein the auxiliaryline is connected to the second portion of the auxiliary electrodethrough a contact hole.
 2. The organic light emitting display apparatusaccording to claim 1, wherein the auxiliary line is disposed between aplurality of the anode electrodes.
 3. The organic light emitting displayapparatus according to claim 1, wherein: the partition wall includeseaves covering the separation space, and a first portion of the eaves ina first direction is separated from the bank by a certain distance, anda second portion of the eaves in a second direction intersecting thefirst direction is supported by the bank.
 4. The organic light emittingdisplay apparatus according to claim 3, wherein the partition wallincludes: a first partition wall on the second portion of the auxiliaryelectrode; and a second partition wall on the first partition wall toact as the eaves.
 5. The organic light emitting display apparatusaccording to claim 4, wherein the contact hole which connects theauxiliary electrode to the auxiliary line does not overlap the firstpartition wall.
 6. The organic light emitting display apparatusaccording to claim 4, wherein: a first portion of the first partitionwall in the first direction is separated from the bank by the certaindistance, and a second portion of the first partition wall in the seconddirection is connected to the bank on the auxiliary electrode.
 7. Theorganic light emitting display apparatus according to claim 6, whereinthe second partition wall in the second direction is supported by thesecond portion of the first partition wall and the bank.
 8. The organiclight emitting display apparatus according to claim 6, wherein a widthof a top of the second partition wall is greater than a width of abottom of the second partition wall on the first partition wall.
 9. Theorganic light emitting display apparatus according to claim 6, whereinthe second portion of the auxiliary electrode is exposed in a regionbetween the second portion of the first partition wall and the bank. 10.The organic light emitting display apparatus of claim 6, wherein thecathode electrode is connected to the second portion of the auxiliaryelectrode through the region between the second portion of the firstpartition wall and the bank.
 11. The organic light emitting displayapparatus according to claim 1, wherein the cathode electrode isconnected to the second portion of the auxiliary electrode under thefirst portion of the eaves.
 12. The organic light emitting displayapparatus according to claim 4, wherein the first partition wall is onthe same layer as the bank.
 13. The organic light emitting displayapparatus according to claim 2, wherein: the auxiliary line has a stripestructure wherein a plurality of the auxiliary lines are arranged in onedirection, or a mesh structure wherein a plurality of auxiliary linesare arranged in two directions to intersect each other.
 14. The organiclight emitting display apparatus according to claim 1, furthercomprising a thin film transistor on the substrate, the thin filmtransistor including a source electrode, wherein the auxiliary line ison the same layer as the source electrode.
 15. The organic lightemitting display apparatus according to claim 1, wherein: the anodeelectrode includes a first anode electrode and a second anode electrode,the second anode electrode covering a top surface and a side surface ofthe first anode electrode; and the auxiliary electrode includes a firstauxiliary electrode and a second auxiliary electrode, the secondauxiliary electrode covering a top surface and a side surface of thefirst auxiliary electrode.
 16. The organic light emitting displayapparatus according to claim 1, wherein the auxiliary electrode is onthe same layer as the anode electrode.
 17. The organic light emittingdisplay apparatus according to claim 1, further comprising a connectionline on the auxiliary line and connected to the auxiliary line, theconnection line connected to the auxiliary electrode.
 18. The organiclight emitting display apparatus according to claim 17, wherein theconnection line is connected to the auxiliary electrode through thecontact hole.
 19. The organic light emitting display apparatus accordingto claim 18, wherein the partition wall includes: a first partition wallon the second portion of the auxiliary electrode; and a second partitionwall on the first partition wall to act as the eaves, wherein thecontact hole which connects the auxiliary electrode to the auxiliaryline does not overlap the first partition wall.
 20. The organic lightemitting display apparatus according to claim 17, further comprising athin film transistor on the substrate, the thin film transistorincluding a source electrode, wherein the auxiliary line is on the samelayer as the source electrode.